In Doctor Who, a “serial” is a televised adventure released over multiple episodes, such as The Trial of a Time Lord (Robert Holmes, Philip Martin and Pip Baker and Jane Baker), which is fourteen episodes long, as opposed to An Unearthly Child (Anthony Coburn), which I consider one episode separate from the following three, regardless of how the BBC market it. Sometimes, a serial’s released in conjoined form as an extended episode, and this gives us the “omnibus”.
The first omnibus was The Dæmons Omnibus (Guy Leopold), which itself condensed five episodes into a single one-hundred-and-twenty-five minute feature. Broadcast by BBC One on 28th December 1971 (the serial finished on 19th June), it was promoted in Radio Times as the first occurrence of a Doctor Who serial being broadcast collectively. Prior to season seven, BBC One broadcast Doctor Who fourty-eight weeks of the year, with no need to fill the four week break. The Dæmons Omnibus achieved a 10.5 million ratings, prompting BBC One to broadcast an omnibus edition of one serial from every subsequent season, which lasted until the Tom Baker era. BBC Four rebroadcast The Dæmons Omnibus in two parts on 21st and 22nd October 2007.
When BBC Video released Doctor Who on home video, Revenge of the Cybermen (Gerry Davis) featured the omnibus format as accepted was first released in the Japan in December 1983. Previous releases had either compressed the four episodes into an hour, or simply been released-as-broadcast. But the serial format wasn’t first released until the United States December 1986 VHS release, which was also released thirty-six months later in the United States.
Terror of the Zygons (Robert Banks Stewart) was also released in serial format on VHS in Australia in April 1987.
The same was applied to Pyramids of Mars (“Stephen Harris“) when released on VHS in the UK in February 1985.
But the VHS release of The Brain of Morbius (“Robin Bland“) on VHS in the UK in July 1984 was only arguably an omnibus edition, as any re-edited releases were cut-down to less than an hour to censor what was considered material too mature for home media.
The VHS release of The Deadly Assassin in the US in March 1989 was an uncensored omnibus edition, released two years before the UK.
Like The Dæmons, The Robots of Death (Chris Boucher), was broadcast as an omnibus in two parts but was also released on VHS in one part. The omnibus was broadcast on 24th and 31st of December 1977 as a pair of fifty minute episodes, the first time this was done, despite being the norm today. The UK VHS release in February 1995 was as one feature-length episode.
The Talons of Weng-Chiang was another serial censored when being serialised. A sequence involving nunchaku was edited-down due to them being classed as illegal weapons in the United Kingdom. Doctor Who breaking into the opium den by pushing the key through the lock and pulling it from under the door with paper was protested, but the BBC persuaded the British Board of Film Classification to retain it due the trick generally not working in practice.
Finishing on 16th March 1982, Earthshock (Eric Saward) was shown as a two-part omnibus on 9th and 16th August 1982.
The next Doctor Who serial wouldn’t be released until 2009. Dreamland (Phil Ford) was originally broadcast in short segments across six days from 21st November 2009 to 27th November 2009. Together, they formed a single-length episode, and this was broadcast as a whole on 5th December 2009. All subsequent releases used the omnibus format, but each original mini-episode is available to view on BBC iPlayer.
A similar distribution method occurred with Pond Life (Chris Chibnall). These were released on BBC Red Button over 27th August 2012 – 31st August 2012 to promote the launch of season twenty-three. The omnibus version was then released by the BBC on YouTube.
And finally – it’s been announced that BBC One HD will broadcast an omnibus of The Magician’s Apprentice/The Witch’s Familiar (Steven Moffat) on Sunday after the conclusion of the two thirds. Whether this will carry-over remains to be seen, especially as this season is essentially a series of paired episodes that are long-enough to be feature length. Personally, I think they should do this with other two-parters. I guess we’ll see in a fortnight. Either that or it’s in reaction to the low ratings for The Magician’s Apprentice, despite live ratings no longer mattering as much as they used to. There’s already been two encores, and those ratings are to be consolidated, along with DVR and online catchup. Another thing could be that these two episodes were screened in Cardiff before their television broadcast, and the BBC may want to make it count.